Thank you very much billbillt.
As promised the protocol is the following:
The samples (left is a chicken femur and right bone unknown origin from a pig)

First I tried the femur but was only able to section it in half (still trying on it)

For the pig bone I used a scalpel and tweezers to remove a small piece

After I used fine sandpaper to grind and at the end polish the sample

The sample was 0.132 mm thick when I decided to stop because it seemed to fragile to polish more
I mounted the bone in glycerin because of its high RI and the fact that glycerin is used as a clearing agent for bone (making the sample more transparent)
The sample showed great details using different filters and didn't require staining
